Ok when should i txt back?

ok well me and this guy are really close now. im pretty sure he likes me and i think i may be startin to like him too. anyways i've been away for the past few days and he just got a new phone but i didn't get the chance to get his new #, so i didn't get a chance to talk to him for awhile. so right before i whas about to go to sleep last nite he started talkin to me on aim. he gave me his new # and told me to text him sometime like 3 times..so i was wonderin do i need to text him like right away or maybe just wait a day or two? im just confused about him right now. thanks for your help(: